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The motivation behind this study is to fabricate novel nanocomposite materials with stronger dielectric characteristics to be applied in electronic devices. The chemical oxidative polymerization technique was employed to fabricate the PET/(PPy-Ag) polymer composite films. These films consist of silver nanoparticles (AgNPs) and polypyrrole (PPy), and the blend (PPy-Ag) is then deposited on the polyethylene terephthalate (PET) substrate. The choice of method depends on the desired application, the properties of the polymer and the level of nanoparticle dispersion required. The characterization methods, Fourier-transform-infrared spectroscopy (FTIR) and energy dispersive X-ray (EDX) were utilized in this study. The EDX data show that the PET/(PPy-Ag) is successfully fabricated with elements C, N, O and Ag, with weight ratios of 15.76%, 8.92%, 65.88% and 9.44%, respectively. The influence of (PPy-Ag) on the conductivity and surface wettability of PET was evaluated. The surface-free energy and adhesion work were determined using contact angle measurements. The surface-free energy increased from 41.64 to 60.24mJ/m² and the water adhesion work increased from 98.78mJ/m² for PET/(PPy-Ag)-1 to 121.01mJ/m² for PET/(PPy-Ag). Moreover, the conductivity enhanced from $6.2\times 10^{-9}$S.cm${}^{-1}$ for PET to $2.4\times 10^{-6}$S.cm${}^{-1}$ for (PPy-Ag)/PET. By modifying the properties of the composite PET/(PPy-Ag), the results demonstrated that the fabricated composite can be used as an electronic and industrial device.

Iron silver oxide (Ag_x${\text{Fe}}_{2-x}$O₃; $0<x<2$) structure for photoelectrochemical (PEC) water splitting was grown by RF–DC co-sputtering of an iron–silver target in argon/oxygen plasma mixtures at 300°C, followed by thermal annealing at 560°C. The chemical composition and structure of the deposited film can be tuned by controlling the metal doping and the annealing temperature. The thermal treatment extensively improves the PEC water-splitting performances of the films. XRD patterns of Ag_xFe${}_{2-x}$O₃ shown in the figure can be indexed to the hexagonal structure of silver oxide and the rhombohedral structure of hematite and new X-ray Diffraction (XRD) peaks of Ag_xFe${}_{2-x}$O₃ structure. The annealing and doping process seems to cause a serious change in the crystal structure of the thin film, it showed a serious change in its electrical properties. The electrical parameters of resistance for thin films were measured using the Hall measurement method at room temperature. With Hall measurements, the n-type carrier concentration of the Fe₂O₃ structure was calculated, and it was observed that its resistance was 1M$\mathrm{\Omega }$. Likewise, it was observed that Ag_xFe${}_{2-x}$O₃ exhibited an n-type carrier concentration, and its resistance was calculated to be 0.5M$\mathrm{\Omega }$. The conductivity change is based on silver doping. The doping process seems to cause a change in the bandgap of the thin film, it showed a change in its optical properties. The film’s optical absorption was measured by UV–Vis photo spectroscopy. Subsequently, the structural and topographic properties of Ag_xFe${}_{2-x}$O₃ structures were investigated by high-precision characterization devices.

In this study, metal oxides of Strontium oxide (SrO) and Lanthanum oxide (La₂O₃) were incorporated into a polymer blend of polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and polyethylene glycol (PEG). Specifically, the blends PVA-PVP-PEG, PVA-PVP-PEG-SrO, PVA-PVP-PEG-La₂O₃, and PVA-PVP-PEG-SrO-La₂O₃ were prepared using casting techniques enhanced by ultrasonic casting methods. The resulting polymer membranes exhibited both semi-crystalline and amorphous characteristics, with the addition of SrO and La₂O₃ leading to prominent crystalline peaks. The electrical properties of these polymer blends were analyzed using impedance spectroscopy and an I-V source meter, which allowed for the determination of their resistance ranges. Notably, the PVA-PVP-PEG-SrO-La₂O₃ membrane exhibited a significant elongation of 102.6%, as indicated by Young’s modulus measurements, underscoring its potential use as an active layer for flexible electronics applications.

Impedance spectroscopy studies of calcium doped (Ca=0.01, 0.05, 0.1) sodium bismuth titanate (NBT), that is, (Na_1/2Bi_1/2)_1-xCa_xTiO₃ (NBCT) solid solution are studied as a function of temperature (RT — 575°C) and frequency (100 Hz–1 MHz). The electrical properties and equivalent circuit parameters of Ca doped NBT, and it's bulk and grain boundary effects are studied with impedance spectroscopy as a non-destructive testing tool.

Electronic structure calculations have been carried out using Extended Hückel tight-binding method for 2H—MoTe₂ for the cases both unrotated and with rotated planes. It has been found that relative rotations of the tellurium layers ranging from 5 to 16 degrees have the same total energies and total energies/atom as the unrotated structure. Moreover, an increased in metallic behavior has been observed, as long as the degrees of rotated planes are increased. Finally, good agreement has been found among previous experimental measurements in the diffraction pattern of irradiated MoTe₂ and our calculated 5, 6 and 7 degrees of rotations.

IZO films were deposited onto polyethylene terephthalate (PET) substrate at room temperature by the inclination opposite target type DC magnetron sputtering equipment. In this paper, SiO or SiON thin films of about 20nm thickness were introduced as buffer layers between the IZO thin films and the PET substrate. Electrical resistivity, transmittance and surface uniformity properties were investigated. It is clear that the film surface roughness of multilayer thin films was less than that of IZO monolayer thin films. The surface average roughness (Ra) of the multilayer film with 230nm IZO layer thickness was about 1.6nm, and that of IZO monolayer film was 2.4nm. All of the multilayer samples had high optical transmittance (about 90%) in the visible region. Of particular note, the transmittance of multilayer films was slightly higher than that of monolayer films when the IZO layer was thicker than 200nm. High electrical conductivity was also achieved with thick films.

In the present work, comparative study of the dielectric behavior of Mn_0.4Zn_0.6Fe₂O₄ ferrite synthesized with and without H₂O₂ (hydrogen peroxide) has been presented. The dc resistivity has been improved by the citrate precursor method as compared to the ceramic method, and it is further improved by the addition of H₂O₂, which acts as a strong oxidizing agent. We have shown by means of X-ray diffraction that the resulting ferrite is made up of nanocrystallites and the average size of these nanocrystallites–calculated by Scherrer's formula–depends on the polarizer. The average particle size was found to be ~70 nm with H₂O₂ and ~88 nm without H₂O₂. The particle size is further confirmed by scanning electron microscopy. Both the results are found to be in good agreement. The decrease in dielectric constant and dielectric loss factor by addition of oxidizing agent is justified by inverse proportionality between the resistivity and dielectric constant. Possible mechanisms contributing to these processes have been discussed.

Nitrogen incorporated hydrogenated amorphous carbon (a-C:N:H) thin films have been deposited by microwave surface-wave plasma chemical vapor deposition on silicon and quartz substrates, using helium, methane and nitrogen (N₂) as plasma source. The deposited a-C:N:H films were characterized by their optical, structural and electrical properties through UV/VIS/NIR spectroscopy, Raman spectroscopy, atomic force microscope and current-voltage characteristics. The optical band gap decreased gently from 3.0 eV to 2.5 eV with increasing N₂ concentration in the films. The a-C:N:H film shows significantly higher electrical conductivity compared to that of N₂-free a-C:H film.

We have carried out thermally stimulated current (TSC) measurements on as-grown Tl₂Ga₂S₃Se layered single crystals in the temperature range 10–60 K with different heating rates of 0.6–1.5 K s¹. The data were analyzed by curve fitting, initial rise, and peak shape methods. The results were in good agreement with each other. Experimental evidence was obtained for trapping center in Tl₂Ga₂S₃Se crystal with activation energy of 11 meV. The capture cross section and concentration of the traps were found to be 1.5 × 10^-23cm² and 1.44 × 10¹⁰cm^-3, respectively. Analysis of the TSC data at different light excitation temperatures leads to a value of 18meV/decade for the traps distribution.

Transparent and conducting SnO₂ thin film has been produced on quartz substrate using rapid thermal oxidation of pure Sn in air at different oxidation temperature and oxidation time. The transmittance T in the visible and NIR was investigated, the allowed direct energy gap was determined to be 3.18 eV at optimum condition of 600° and 90 s. The dependence of the resistivity on the film thickness and oxidation time has been studied. The optimum thickness of high transmittance and lowest resistivity is about 150 nm for SnO₂ were ρ = 2 × 10^-2Ω cm and T = 88%.

In this study, we have developed the method for obtaining a conductive DLC layer on glass substrate of 30×30mm size by adding Nitrogen or Silane gas during CVD(Chemical Vapor Deposition) growth. The growth rate and electrical conductivity were investigated under different plasma deposition condition. In addition, we measured the optical transmittance spectra of the films. From the measurements of optical transmittance in range of 300 to 1150 nm wavelength, an optical transmittance is obtained from 80% to 90% from the DLC films grown with lower gas flow rates. The characteristic of DLC films were evaluated by various techniques including alpha step surface profiler, micro Raman spectroscope, X-ray diffraction(XRD) and Nano- indentation.

In this work, we synthesized chromium-doped CdS nanowires by simple vapor deposition. And the current–voltage characteristics of single CdS nanowire have been studied. The results from electrical transport measurements on the field-effect transistors showed that the nanowire was an n-type semiconductor. In addition, the Au/CdS nanowire device exhibited clear diode-like behavior, and a thermally-assisted tunneling mechanism, which dominates the transport of carriers above the metal–semiconductor contact in the diode, was discussed in detail.

[X]%BaTiO₃[100-x]%CoFe₂O₄ composites (x = 0, 20, 40, 60, 80, and 100) were prepared by the general ceramic method. X-ray diffraction patterns and IR spectra confirmed the presence of two phases beside identified phase in the composites with (x% = 40-80%BaTiO₃).

The temperature variation of conductivity was mainly attributed to change of the drift mobility rather than to the variation of charge carrier concentration. All the composites showed p-type behaviors in the range of temperature 300–400 K. For T > 400 K all composites showed n-type behavior. At this high temperature, the conduction is mainly due to Fe³⁺→Fe²⁺. Hence, there is a p–n transition.

The variation of dielectric constant as a function of temperature showed a peak value at the Curie temperature (around 390 K) of ferroelectric phase in composites. It is also noted that the phase transition temperature T_c varied for different composites.

The relation between charge carrier mobility log(μ_d) versus (1/T) is nearly linear supporting the polaron hopping model for the conduction. The activation energies calculated from resistivity and that from mobility are in close agreement indicating localized model of charge carrier.

The initial permeability increased with increasing temperature which is due to the activation of hopping electrons between Fe³⁺ and Fe²⁺ giving rise to the magnetic moment of the composites.

The crystal structure at room temperature (RT), thermal expansion from RT to 1000°C and electrical conductivity, from RT to 600°C, of the perovskite-type oxides in the system Pr_1-xSr_xFeO₃(x = 0, 0.2, 0.4, 0.6) were studied. All the compounds have the orthorhombic perovskite GdFeO₃-type structure with space group Pbnm. The lattice parameters were determined by X-ray powder diffraction. The Pseudo cubic lattice parameter decreases with an increase in x, while the coefficient of linear thermal expansion increases. The thermal expansion is almost linear for x = 0 and 0.2. The electrical conductivity increases with increasing x while the activation energy decreases. The electrical conductivity can be described by the small polaron hopping conductivity model.

The microstructure and nonohmic properties of SnO₂–Ta₂O₅–ZnO based ceramics sintered at 1450°C for 2 h were investigated in accordance with TiO₂ content (0–8 mol%). Without TiO₂ the prepared sample is nonstoichiometric SnO₂ semiconductor with excessive oxygen; but for the samples doped with TiO₂, Sn_0.9Ti_0.1O₂ phase can be identified, and the incorporation of TiO₂ into the ternary system SnO₂–Ta₂O₅–ZnO ceramics can compensate the defects of Sn⁴⁺ ions loss, promote the sample densification, and facilitate the growth of SnO₂ grains. After 4.0 mol% of TiO₂ is doped, the samples present no precipitated substances residing in the grain juncture, resulting in varistors with maximum nonlinear exponent of 21, varistor voltage of about 1000 V/mm, and minimum leakage current of 100 μA/cm², which are promising in high-voltage applications. The improvement in nonohmic performance of the varistors after the doping of TiO₂ is mainly attributed to the increase in effective barrier height in grain boundary, which can be supported by the decrease in band gap caused by defects and impurities from periodic density function theory calculation.

The microstructure and nonohmic properties of SnO₂–Ta₂O₅–TiO₂-CuO varistor system were investigated. The proposed samples were doped with different contents of CuO (0–6 mol%) and sintered at 1400°C for 2 h with conventional ceramic processing method. In all the samples, the commonly identified phase was SnO₂ (rutile); however, with increasing doping amount of CuO, the peaks of CuO phase emerged in the X-ray diffraction (XRD) patterns. Scanning electron microscopy (SEM) examination on the fractured surfaces of the samples revealed that a minor amount of CuO dopant can facilitate the sintering of the varistor ceramics, but excessive CuO would mainly segregate at grain-boundaries. The doped CuO may also act as a modifier in the SnO₂ based varistors. The measured electric-field versus current-density characteristics of the samples indicated that both nonlinear exponent and varistor voltage increased with increasing doping amount of CuO up to 3 mol% and then decreased with excessive CuO.

We have investigated strain mediated magnetoelectric (ME) coupling and impedance properties in 0.5Zn${}_{0.3}$Ni${}_{0.7}$Fe₂O₄–0.5HoMnO₃ nanocomposites at room-temperature. The ME voltage is measured in both longitudinal and transverse direction at a frequency of 173 Hz. The impedance, real and imaginary parts of impedance and dielectric constant have been carried out in presence of DC magnetic field. With the application of magnetic field, slight decrease in dielectric constant has been observed. The impedance, real and imaginary parts of impedance are found to increase with the increase in the applied magnetic field. Nyquist plots have been fitted using three parallel combinations of resistances–capacitance circuits. Fitted parameters show the dominant role of grain boundaries, grains and interface of two types of grains of the sample.

The Cd${}_x$Zn${}_{1-x}$O thin films have been deposited on glass and Si substrates at room-temperature with different Cd contents (x = 0, 2%, 4% and 6 wt.%) by pulsed laser deposition (PLD) technique. X-ray diffraction (XRD) analyses evidenced that the films possess polycrystalline and a hexagonal ZnO crystal structure for x = 0, 2% and 4% with a preferred orientation in the a-axis (101) direction, while films with a mixed hexagonal and cubic structure was revealed for x = 6 wt.%. Electrical measurement presented that the resistivity decreased with increased temperature and concentration of Cd. The deliberated activation energy was reduced was from 0.224 to 0.113 eV with increase doping concentration. Current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the fabricated Cd${}_x$Zn${}_{1-x}$O/p-Si heterojunction varied with the applied bias and the Cd concentration. The results of the values of built-in potential (V${}_{\mathrm{\text{bi}}}$) and the ideality factor (n) increased with raising Cd concentration.

In this work, transparent and conductive Al-doped ZnO (AZO) nanofilms were prepared on quartz substrate by ultrasonic spray pyrolysis (USP) method. The effects of Al/Zn atomic ratios on the micro-structural, morphological, optical photoluminescence and electrical properties of AZO thin films were effectively investigated. All the prepared samples showed hexagonal wurtzite structure. The scanning electron microscopy (SEM) showed that the surface morphology of all samples changed with the substrate temperature. The average transmittance of all AZO samples was higher than 85% in the visible region. The photoluminescence (PL) spectrum of the samples showed that the near band edge emission in PL spectra shifted to shorter wavelengths with increasing Al-doped concentration. The lowest sheet resistance was obtained for the samples prepared with 4% at. Al-doped value. The electrical conductivity of AZO films was improved by Al doping, which allowed their use as optoelectronic materials.

In this communication, structural and electrical properties of rare earth oxides La₂O₃ (LO) and LaNdO₃ (LNO) have been studied. To understand the structural properties of the LO and LNO samples, X-ray diffraction (XRD) measurement was carried out at room temperature. The XRD patterns have been analyzed by Rietveld refinement to confirm the single-phase nature of both the samples. The crystal structures of studied samples were created from the derived parameters of Rietveld parameters. The crystal size and lattice strain have been estimated using Williamson–Hall (W–H) plot analysis. Frequency-dependent dielectric constant and loss tangent have been studied for a frequency range of 20 Hz to 2 MHz. To estimate the relaxation time and contribution of the charge carriers in the studied samples, relaxation mechanism and universal dielectric response (UDR) model have been employed. The ac conductivity measurements were carried out for the same frequency range (i.e., 20 Hz to 2 MHz) which has been understood on the basis of Jonscher’s power law. The barrier height has been calculated by fitting the power law. Frequency-dependent impedance behavior has been discussed in the context of grains and grain boundaries for both the samples under study.